Common sense. If something that you know will make someone upset, annoyed or angry, do not post it. If you ask the person to stop it and they do, that is fine, but if they do not that will be considered a rule break. This also includes users who come online and "troll."

Spamming the chat with emoticons or by typing the same thing over and over again.

A banned person may ask an administrator or chat mod to be unbanned if they believe the ban was not justified. You must state the name of the moderator who banned you and what exactly happened and it is best to provide proof (such as screen captures).